发信人: HIFI (~ZZZ), 信区: program 标 题: Re: 公历和农历的关系！ 发信站: 交大兵马俑BBS站 (Sun Jul 11 23:26:28 1999), 转信 【 在 star (光明来到乐) 的大作中提到: 】 ∶ 有这种算法吗？ ∶ 从来没见过 ∶ 有的话我也要一份 ∶ 【 在 ZiXiM (浙客西蒙) 的大作中提到: 】 给你一个delphi的例程： （我也是抄的，算法就请自己分析了.） unit CNYear; interface uses sysutils; type TCNDate = Cardinal; function DecodeGregToCNDate(dtGreg:TDateTime):TCNDate; function GetGregDateFromCN(cnYear,cnMonth,cnDay:word;bLeap:Boolean=False): TDateTime; function GregDateToCNStr(dtGreg:TDateTime):String; function isCNLeap(cnDate:TCNDate):boolean; implementation const cstDateOrg:Integer=32900; //公历1990-01-27的TDateTime表示 对应农历19 90-01-01 const cstCNYearOrg=1990; const cstCNTable:array[cstCNYearOrg..cstCNYearOrg + 60] of WORD=( // unsigned 16-bit 24402, 3730, 3366, 13614, 2647, 35542, 858, 1749, //1997 23401, 1865, 1683, 19099, 1323, 2651, 10926, 1386, //2005 32213, 2980, 2889, 23891, 2709, 1325, 17757, 2741, //2013 39850, 1490, 3493, 61098, 3402, 3221, 19102, 1366, //2021 2773, 10970, 1746, 26469, 1829, 1611, 22103, 3243, //2029 1370, 13678, 2902, 48978, 2898, 2853, 60715, 2635, //2037 1195, 21179, 1453, 2922, 11690, 3474, 32421, 3365, //2045 2645, 55901, 1206, 1461, 14038); //2050 //建表方法： // 0101 111101010010 高四位是闰月位置,后12位表示大小月,大月30天,小月29 天, //闰月一般算小月,但是有三个特例2017/06,2036/06,2047/05 //对于特例则高四位的闰月位置表示法中的最高为设置为1 特殊处理用wLeapNormal变 量 // //2017/06 28330->61098 2036/06 27947->60715 2047/05 23133->55901 //如果希望用汇编,这里有一条信息:农历不会滞后公历2个月. //将公历转换为农历 //返回:12位年份+4位月份+5位日期 function DecodeGregToCNDate(dtGreg:TDateTime):TCNDate; var iDayLeave:Integer; wYear,wMonth,wDay:WORD; i,j:integer; wBigSmallDist,wLeap,wCount,wLeapShift:WORD; label OK; begin result := 0; iDayLeave := Trunc(dtGreg) - cstDateOrg; DecodeDate(IncMonth(dtGreg,-1),wYear,wMonth,wDay); if (iDayLeave < 0) or (iDayLeave > 22295 )then Exit; //Raise Exception.Create('目前只能算1990-01-27以后的'); //Raise Exception.Create('目前只能算2051-02-11以前的'); for i:=Low(cstCNTable) to High(cstCNTable) do begin wBigSmallDist := cstCNTable[i]; wLeap := wBigSmallDist shr 12; if wLeap > 12 then begin wLeap := wLeap and 7; wLeapShift := 1; end else wLeapShift := 0; for j:=1 to 12 do begin wCount:=(wBigSmallDist and 1) + 29; if j=wLeap then wCount := wCount - wLeapShift; if iDayLeave < wCount then begin Result := (i shl 9) + (j shl 5) + iDayLeave + 1; Exit; end; iDayLeave := iDayLeave - wCount; if j=wLeap then begin wCount:=29 + wLeapShift; if iDayLeave < wCount then begin Result := (i shl 9) + (j shl 5) + iDayLeave + 1 + (1 shl 21); Exit; end; iDayLeave := iDayLeave - wCount; end; wBigSmallDist := wBigSmallDist shr 1; end; end; //返回值: // 1位闰月标志 + 12位年份+4位月份+5位日期 (共22位) end; function isCNLeap(cnDate:TCNDate):boolean; begin result := (cnDate and $200000) <> 0; end; function GetGregDateFromCN(cnYear,cnMonth,cnDay:word;bLeap:Boolean=False): TDateTime; var i,j:integer; DayCount:integer; wBigSmallDist,wLeap,wLeapShift:WORD; begin // 0101 010010101111 高四位是闰月位置,后12位表示大小月,大月30天,小月 29天, DayCount := 0; if (cnYear < 1990) or (cnYear >2050) then begin Result := 0; Exit; end; for i:= cstCNYearOrg to cnYear-1 do begin wBigSmallDist := cstCNTable[i]; if (wBIgSmallDist and $F000) <> 0 then DayCount := DayCount + 29; DayCount := DayCount + 12 * 29; for j:= 1 to 12 do begin DayCount := DayCount + wBigSmallDist and 1; wBigSmallDist := wBigSmallDist shr 1; end; end; wBigSmallDist := cstCNTable[cnYear]; wLeap := wBigSmallDist shr 12; if wLeap > 12 then begin wLeap := wLeap and 7; wLeapShift := 1; //大月在闰月. end else wLeapShift := 0; for j:= 1 to cnMonth-1 do begin DayCount:=DayCount + (wBigSmallDist and 1) + 29; if j=wLeap then DayCount := DayCount + 29; wBigSmallDist := wBigSmallDist shr 1; end; if bLeap and (cnMonth = wLeap) then //是要闰月的吗? DayCount := DayCount + 30 - wLeapShift; result := cstDateOrg + DayCount + cnDay - 1; end; //将日期显示成农历字符串. function GregDateToCNStr(dtGreg:TDateTime):String; const hzNumber:array[0..10] of string=('零','一','二','三','四','五','六', '七','八','九','十'); function ConvertYMD(Number:Word;YMD:Word):string; var wTmp:word; begin result := ''; if YMD = 1 then begin //年份 while Number > 0 do begin result := hzNumber[Number Mod 10] + result; Number := Number DIV 10; end; Exit; end; if Number<=10 then begin //可只用1位 if YMD = 2 then //月份 result := hzNumber[Number] else //天 result := '初' + hzNumber[Number]; Exit; end; wTmp := Number Mod 10; //个位 if wTmp <> 0 then result := hzNumber[wTmp]; wTmp := Number Div 10; //十位 result:='十'+result; if wTmp > 1 then result := hzNumber[wTmp] + result; end; var cnYear,cnMonth,cnDay:word; cnDate:TCNDate; strLeap:string; begin cnDate:= DecodeGregToCNDate(dtGreg); if cnDate = 0 then begin result := '输入越界'; Exit; end; cnDay := cnDate and $1F; cnMonth := (cnDate shr 5) and $F; cnYear := (cnDate shr 9) and $FFF; //测试第22位,为1表示闰月 if isCNLeap(cnDate) then strLeap:='(闰)' else strLeap := ''; result := '农历' + ConvertYMD(cnYear,1) + '年' + ConvertYMD(cnMonth,2) + '月' + strLeap + ConvertYMD(cnDay,3) ; end; end.
